A mass airflow (“MAF”) sensor is generally used to determine a mass flowrate of air entering a fuel-injected internal combustion engine of a motor vehicle. Information regarding the mass flowrate of air is necessary for an engine control unit (ECU) to balance and deliver a correct quantity of fuel to the engine in view of variations in air density due to changes in ambient temperature and pressure. Unfortunately, those seeking to learn about how a MAF sensor operates must either work in a mechanic's garage, or teach themselves on their own time, using their own resources. Furthermore, most shops, garages and dealerships lack an ability to adequately evaluate MAF sensor calibrations. As a result, many misconceptions exist regarding the functionality of MAF sensors and the inter-relation of MAF sensors with various components under the hood of a motor vehicle, such as an air filter.
One common misconception is that oil from an air filter may cause failure of a MAF sensor under normal driving conditions. In reality, however, MAF sensor failure may be attributable, in many instances, to any of various issues that are unrelated to the air filter. For example, a MAF sensor may fail due to trace levels of silicone potting compound that is used in the manufacturing process of MAF sensors, delamination of sensing elements in the thin film of some sensors, and/or the “chimney effect” wherein certain compounds migrate up the intake tract and coalesce on any of various surfaces, especially surfaces of sensing elements. In essence, the MAF sensor may contaminate itself, irrespective of any oil from the air filter. Moreover, in some instances, contamination may be due to motor oil carried with blow-by gases; a condition where oil vapor from combustion is re-circulated into the vehicle's intake tract. Such misconceptions have led many motor vehicle owners to be mistakenly advised to purchase a new MAF sensor in addition to replacing a dirty air filter with a new air filter.
In general, demonstrating causes of MAF sensor failure is problematic due to a difficulty in illustrating how various components cooperate during operation of an internal combustion engine. Furthermore, many authorized dealerships, as well as members of the automotive industry, simply are left to speculate regarding a root cause of MAF sensor failure, due to a lack of test equipment necessary to demonstrate MAF sensor failure. As such, there is a need for a portable MAF training module that may be configured to demonstrate operation of a MAF sensor during various desired levels of air flow.